The present invention relates to a plastic film having an antistatic coating on at least one surface thereof.
While plastic films are well known and exhibit good service value, the films have the disadvantage of an undesirably high electrostatic chargeability. Films are known in which either an antistatic agent is worked into the mixture of film-forming material, or a thin layer of antistatic agent is applied to the surface, in order to avoid this disadvantageous property. With the first-mentioned type, either the achieved effect is low or, if higher amounts of antistatic agent are added, the mechanical properties of the films are adversely affected. The application of an antistatic layer gives better results. The antistatic agents used are, in most cases, water-soluble, low molecular weight products or polymeric products. However, addition of the antistatic layer results in a film having only a limited resistance to moisture or water. Moreover, these layers can be easily abraded by mechanical means which render the film ineffective.
If conventional antistatic agents are used in combination with binders, the films are more resistant to mechanical strain; however their antistatic action is correspondingly reduced. Furthermore, the action of water diminishes the improved binder-promoted resistance.